About 60 to 80 percent of our immune system lives in our gut. Imbalances in the gut’s microbiome (which is primarily made up of bacteria) lead to digestive issues, while many many other potential effects can be felt throughout the body—from feelings of fatigue to depression, thyroid dysfunction, autoimmunity, and a host of skin issues. Conditions like rosacea, psoriasis, eczema, and acne are really inflammatory conditions, and often a manifestation of something that is happening deeper within the body. When you fix the gut (which, depending on your health, might include getting rid of an infection like Candida, eating a clean diet, and taking a probiotic), skin issues often resolve as well.
"I usually recommend Garden of Life, BioK or Megafoods brand," says Shapiro. "I also recommend starting with about 30 billion CFU and making sure your supplement has at least 12 different strains. And if you don't eat a diet high in fruits, vegetables, nuts, seeds, and whole grains that provide fiber for the probiotics to live off of, make sure you're the one you are taking contains prebiotics as well.
That said, supplements with higher numbers of CFUs are sometimes used to treat conditions such as irritable bowel syndrome (IBS), allergies, and respiratory illness. While probiotics have generally been found to be safe for most people with normal immune systems, too much can cause gas and upset stomach. We narrowed our search to supplements with dosages between 1 billion and 100 billion CFUs.
With Prebiotin, you can easily add prebiotic fiber to your diet without worrying about eating huge amounts of troublesome foods or hunting down hard-to-find ingredients. You also won’t have to worry about loading up on high-calorie foods that can negatively affect any effort to lose weight. Combining Prebiotin prebiotic fiber with a diet enriched with probiotic foods can only help your effort to positively influence the bacterial balance in your lower gut.
“Microbiome” refers to the trillions of bacteria and microorganisms that live on and in our individual bodies. “There’s increased recognition of the various ways that the microbiome affects our health,” Lebwohl tells me. “And with that recognition comes the true observation that many bacteria are good for us. This goes against the old idea that bacteria equal germs, which equal harm. It turns out that many bacteria keep us healthy and probiotics could potentially support that notion.”
You may have heard some questions over whether SBOs are safe: The NIH has a presumed case report, which hasn’t been 100 percent verified, of someone with Lymphoma getting septicemia from taking a SBO (the organism B. subtilis). Some say that if you have leaky gut, you should heal it before supplementing with SBOs. If you are immunocompromised or have cancer, you can consult with a physician first to be safe.
The U.S. Clinical Guide to Probiotic Products1, Canadian Guide to Probiotic Supplements2 and the WGO Global Guidelines for Probiotics and Prebiotics3 provide suggested effective amounts of specific strains for treating certain health conditions, such as constipation or IBS. All 37 products listed the species of bacteria they contained, but only 14 listed amounts of individual strains. We found that 9 of those 14 products provided beneficial bacteria at effective levels. The Center for Responsible Nutrition recommends4 the industry move toward specifying strains as a best-practice because whether a product works and for what purpose depends on its strains.

Like some of the other probiotics we’ve reviewed, the HyperBiotics PRO-Women Probiotics with Cranberry Extract and D-Mannose do not need to be refrigerated in between uses. What sets this particular formula apart though is its longer shelf life made possible by the patented HyperBiotics ‘LiveBac’ manufacturing process. In fact, the HyperBiotics PRO-Women Probiotics formula can usually last for more than a year when stored in normal indoor conditions!


You may have heard some questions over whether SBOs are safe: The NIH has a presumed case report, which hasn’t been 100 percent verified, of someone with Lymphoma getting septicemia from taking a SBO (the organism B. subtilis). Some say that if you have leaky gut, you should heal it before supplementing with SBOs. If you are immunocompromised or have cancer, you can consult with a physician first to be safe.
We found the most evidence linking strains to antibiotic recovery, immune health, and IBS/IBD relief. We made checklists of the most researched strains that treat those issues (10 strains known to boost general health, six for immune health, seven for antibiotic recovery, and seven for IBS/IBD relief) and dug into ingredient lists to find the supplements containing the highest number of effective strains for each use case.

Jotham Suez, Niv Zmora, Gili Zilberman-Schapira, Uria Mor, Mally Dori-Bachash, Stavros Bashiardes, Maya Zur, Dana Regev-Lehavi, Rotem Ben-Zeev Brik, Sara Federici, Max Horn, Yotam Cohen, Andreas E. Moor, David Zeevi, Tal Korem, Eran Kotler, Alon Harmelin, Shalev Itzkovitz, Nitsan Maharshak, Oren Shibolet, Meirav Pevsner-Fischer, Hagit Shapiro, Itai Sharon, Zamir Halpern, Eran Segal, Eran Elinav. Post-Antibiotic Gut Mucosal Microbiome Reconstitution Is Impaired by Probiotics and Improved by Autologous FMT. Cell, 2018; 174 (6): 1406 DOI: 10.1016/j.cell.2018.08.047
Update: I think this product is being smeared by a competitor! Look at all the reviews in April. Suddenly, a butt ton of not just negative but 1 star reviews. It's uncanny. So, what would compel a competitor to do such a thing? Well, it was the only 50 CFU, enteric coated & 20 strain probiotic on Amazon & it cost about 15 bucks. That, while products far inferior to it were priced for - often times - 2 or 3x as much.
Whether a brand of probiotics works really depends on its quality and your body's own gut. Everyone has a different set of gut flora so try several to see what works for you. Using a brand of at least 40 billion CFU is best. There seems to be some debate as to whether one should use refrigerated or unrefrigerated probiotics. I went with the side that claims unrefrigerated are sturdier and less prone to die off.

On my recent trip to Japan, one thing I noticed was the inclusion of pickled vegetables in almost every traditional Japanese meal. Unfortunately, many Americans don’t consume enough of these probiotic-rich foods and drinks. Even when they do, restoring equilibrium oftentimes requires therapeutic doses of these microorganisms, because most everyone has been on several rounds of antimicrobials. That’s where a probiotic supplement comes in.
Even for healthy people, there are uncertainties about the safety of probiotics. Because many research studies on probiotics haven’t looked closely at safety, there isn’t enough information right now to answer some safety questions. Most of our knowledge about safety comes from studies of Lactobacillus and Bifidobacterium; less is known about other probiotics. Information on the long-term safety of probiotics is limited, and safety may differ from one type of probiotic to another. For example, even though a National Center for Complementary and Integrative Health (NCCIH)-funded study showed that a particular kind of Lactobacillus appears safe in healthy adults age 65 and older, this does not mean that all probiotics would necessarily be safe for people in this age group.
Every day, we’re exposed to toxins and inflammation-causing molecules from food and the environment that negatively impact digestion through pathways, such as leaky gut, known in the medical field as intestinal hyperpermeability. In leaky gut, the tight junctions that are supposed to keep disease-contributing compounds from leaving the digestive system are disrupted, allowing a lot of things through into the bloodstream that don’t belong there.

Even if you’re not sensitive to dairy, though, probiotics that require refrigeration can be inconvenient; but there are now some that don’t need to be kept cold. For example, our probiotics are sealed in nitrogen blister packs to protect them from heat, as well as moisture and oxygen because the air can’t get in. Look for probiotics that are individually packed to protect the live cultures. If they just come in a bottle they could be losing potency from air getting in.
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Overall, Enzymatic Therapy Acidophilus Pearls are a great daily probiotic supplement. They give you a ton of flexibility and is convenient since it doesn’t need to be refrigerated and can be taken with or without food! This probiotic makes on-the-go belly support a breeze. All in all, Enzymatic Therapy Acidophilus Pearls finally make it easy to travel with probiotics, are simple to take, and can give you the piece of mind that the money you’re spending on probiotics isn’t being wasted at the first sign of stomach acid.  Read the full review here… or click here to go buy it now!
Probiotics: Health benefits, facts, and research Every human on the planet has microbes living in their body. While bacteria get a bad reputation, many can promote good health. Probiotics are a type of 'good bacteria' that provide health benefits for the host. The health benefits of probiotics include treatment of diarrhea and irritable bowel syndrome. Read now
Gut flora makes up 70 to 80 percent of the human immune system. Too much bad bacteria can inflame and destroy intestinal walls, enter the bloodstream, and trigger a multitude of health issues — constipation, depression, skin problems, autoimmune disease, and even bad breath. Adding good bacteria protects the digestive tract from the harmful bacteria in sugars, pesticides, and saturated fats.
In a separate study involving 21 healthy volunteers, also published today in Cell, the same group of researchers found that taking probiotics after treatment with broad spectrum antibiotics may actually delay the return of people's normal gut microbiome. This goes against the idea that probiotics can help "repopulate" people's gut bacteria after antibiotics wipe them out.

An imbalance in the gut microbiota is believed to contribute to a number of health problems, particularly gastrointestinal issues, as well as immune dysfunction and infections. The bacterial balance can be disrupted by medical conditions, emotional and physical stress, and, most notably, use of antibiotics, which destroy the good bacteria along with the bad.
In the United States, most probiotics are sold as dietary supplements, which do not undergo the testing and approval process that drugs do. Manufacturers are responsible for making sure they're safe before they're marketed and that any claims made on the label are true. But there's no guarantee that the types of bacteria listed on a label are effective for the condition you're taking them for. Health benefits are strain-specific, and not all strains are necessarily useful, so you may want to consult a practitioner familiar with probiotics to discuss your options. As always, let your primary care provider know what you're doing.
Lebwohl says IBS isn’t just about intestinal distress. For many IBS sufferers, it’s about the way our brain receives messages about pain. He describes the human colon as “almost reptilian” in the way that it contracts and relaxes throughout the day, but says these contractions are usually happening way below our threshold of consciousness, so we don’t even notice. In people with IBS, the neurotransmitters in our gut (yes, we have them in there too) may be sending severe distress signals to the brain about benign contractions happening in digestive tract.
As with other types of supplements, scientists are still discovering the full potential of probiotics. However, when taken regularly, it is believed that they help support digestive health by helping maintain the balance of beneficial and non-beneficial bacteria in your digestive tract. Having a natural balance of good bacteria in the digestive tract can help defend against occasional digestive issues. In addition, probiotics play an important role in supporting immune health, since 70% of the body's immune system is found in the digestive tract.∗
Kefir: This could be the most ideal probiotic dairy product because it contains both bacteria and yeast working together to provide the numerous health benefits. In a recent eight-week study, people with diabetes were given kefir milk containing Lactobacillus casei, Lactobacillus acidophilus, and bifidobacteria vs. conventional fermented milk. The hemoglobin A1C levels were significantly lower in the group consuming the kefir. 

A closer look at the science underlying microbe-based treatments, however, shows that most of the health claims for probiotics are pure hype. The majority of studies to date have failed to reveal any benefits in individuals who are already healthy. The bacteria seem to help only those people suffering from a few specific intestinal disorders. “There is no evidence to suggest that people with normal gastrointestinal tracts can benefit from taking probiotics,” says Matthew Ciorba, a gastroenterologist at Washington University in St. Louis. “If you're not in any distress, I would not recommend them.” Emma Allen-Vercoe, a microbiologist at the University of Guelph in Ontario, agrees. For the most part, she says, “the claims that are made are enormously inflated.”
When shopping for a probiotic, the first things to look at are CFUs count and probiotic strains. CFUs is the acronym for colony forming units, and is the measure of how many probiotic bacteria are capable of dividing to form colonies. In other words, the higher the CFUs, the higher the number of active, live good bacteria. Generally speaking, the higher the CFUs, the better, although there are exceptions.

Most people with diverticulosis have few if any symptoms at all. When people do experience signs and symptoms of diverticulosis (diverticular disease) they may include abdominal pain, abdominal cramps, diarrhea, constipation, and bloating. Diverticulitis is a condition in which diverticuli in the colon rupture. The rupture results in infection in the tissues that surround the colon. Treatment methods for diverticulitis includes prescription medications, and in some cases, diverticulitis surgery.

Candida yeast species, on the other hand, can cause numerous infections in and on you. Although they are usually present in controlled amounts, Candida overcomes your usual defenses and establishes itself when conditions are favorable, such as when you take antibiotics and many beneficial bacteria, which normally would control Candida, are killed. Unlike the Saccharomyces yeasts, which are not invasive, Candida species form hyphae, finger-like projections that penetrate tissues, causing deep infections that are difficult to eliminate. Candida is also able to weaken your immune defenses.


If you suffer from a food allergy or intolerance, make sure to check those labels! Probiotics with these dietary features often say so right on the front of the bottle, but you will also want to take a quick peek at the ingredients list as well. A word to the wise: anyone with a food allergy should also check the manufacturer’s information to ensure that cross-contamination is not likely to have occurred on-site in the packaging facility.
Best Probiotic says that Suprema Dophilus, manufactured and distributed by Vitabase, enjoys the highest customer rating in the market. Specially coated to help the bacteria spread through your entire digestive tract, its website claims over four billion viable cells per capsule, including five lactobacillus strains and three bifidobacteria cultures. Best Probiotic says that Suprema Dophilus also contains fructo-oligosaccarides to increase the life span of the bacteria.
There is also promising research on this species for supporting skin. Ceramides are natural lipids that make up the surface of the skin structure. Depleted ceramide levels are clinically linked with dry and damaged skin. S. Thermophilus was shown to have a beneficial effect on the level of ceramides in the barrier of the skin, which protects underlying tissue from infection, dehydration and chemicals. These skin-supporting microbes also act as antioxidants in the body, trapping reactive forms of oxygen that dry, damage and age the skin [1].
While probiotics have been around as long as bacteria have, they were first officially identified for their health benefits in the early 20th century by Russian-born biologist Élie Metchnikoff. Metchnikoff believed that “good bacteria” like the microbes that produce lactic acid could prolong life and stave off senility, and actually recommended drinking sour milk daily for overall health. While Metchnikoff’s theories were pooh-poohed by many of his contemporaries, the first commercial probiotic, Yakult, hit the market in 1935 and is still on the shelves today.
“​You have all sorts of microbiomes in your body, in the lungs, the oral cavity, the vagina and of course the gut. Everybody was looking at the microbiome as just being about just good bacteria,​”​Afif Ghannoum said.  The elder Ghannoum, who is associated with Case Western Reserve University in Cleveland, OH, showed the importance of the fungal components of those microbiomes, he said.

Probiotics may seem new to the food and supplement industry, but they have been with us from our first breath. During a delivery through the birth canal, a newborn picks up the bacteria Bacteroides, Bifidobacterium, Lactobacillus, and Escherichia coli from his/her mother. These good bacteria are not transmitted when a Cesarean section is performed and have been shown to be the reason why some infants born by C-section have allergies, less than optimal immune systems, and lower levels of gut microflora.


One review of probiotics benefits for necrotizing enterocolitis was bold enough to say, “The results confirm the significant benefits of probiotic supplements in reducing death and disease in preterm neonates. The … evidence indicate that additional placebo-controlled trials are unnecessary if a suitable probiotic product is available.” Regarding sepsis in developing countries (where it is overwhelmingly more common), a 2017 randomized, controlled trial claims that a large number of these cases “could be effectively prevented” if mothers are given a synbiotic (probiotic and prebiotic together) that contains the probiotic strain L. plantarum.
There are both probiotics and prebiotics in fermented foods. I differ from a lot of doctors in that I recommend that patients with infections like Candida and SIBO don’t eat prebiotics until they’ve cleared up the infection—because the prebiotics can feed those infections, too. I find that it’s better to get rid of those infections first, and then add in prebiotics to your diet after. [See here for more from Dr. Myers on treating yeast infections.]
Whether a brand of probiotics works really depends on its quality and your body's own gut. Everyone has a different set of gut flora so try several to see what works for you. Using a brand of at least 40 billion CFU is best. There seems to be some debate as to whether one should use refrigerated or unrefrigerated probiotics. I went with the side that claims unrefrigerated are sturdier and less prone to die off.
Afif Ghannoum said the key insight, one that he called groundbreaking, is that his father’s team found that fungi and microbes were cooperating in the construction of the plaques.  He said election microscope images show the filaments of the fungi being incorporated into the carbohydrate ‘armor’ that the bacteria start to secrete once enough individual cells have gathered at a certain location. Without the addition of the digestive enzyme to their product, he said that the plaques, once adhered to the intestinal wall, would be difficult to attack.
This dairy-free, gluten-free, vegetarian probiotic delivers live microorganisms, protected in stomach acid-resistant capsules to ensure effective delivery throughout your digestive system, from the stomach through your small intestines. The result is the repair and sustained maintenance of your intestinal micro-ecology, which in turn helps support healthy immune response and bowel regularity.
Probiotics seem to be all the rage these days. With many purported benefits and a relatively low risk of side effects, manufacturers are taking advantage of booming business opportunities. Rather than leave your health in the hands of big business, it is important that you be as educated as possible about the best types of probiotics so you can choose what is right for you and your family.
For most of my life, I thought of probiotics as something I’d only drink if I lost a bet. Then stress-induced irritable bowel syndrome (IBS) turned my intestinal tract into a nonstop river of shit—we’re talking weeks of everything I ate shooting straight out my butt in liquid form. The internet said probiotics were my best non-pharmaceutical bet to help my digestive system calm down, so I swallowed my pride (and my first kombucha ever) and kinda sorta saw the light. My IBS wasn’t cured, but probiotics did help me spend less time on the toilet wide-eyed with terror, and more time doing what’s really important in life—watching TV with my family.

On my recent trip to Japan, one thing I noticed was the inclusion of pickled vegetables in almost every traditional Japanese meal. Unfortunately, many Americans don’t consume enough of these probiotic-rich foods and drinks. Even when they do, restoring equilibrium oftentimes requires therapeutic doses of these microorganisms, because most everyone has been on several rounds of antimicrobials. That’s where a probiotic supplement comes in.
CFU: This is the number of "colony forming units" present in each dose, which are measured in the billions. And while more isn't always better, "you want at least 20 to 50 billion CFU," says Dr. Nazareth. Just for reference, a very high dose is 400 CFU, which most experts agree is not necessary unless your health care practitioner specifically recommends this for you. It's also important to check for the guaranteed CFU upon expiration, which should be listed clearly. "Some products only guarantee the CFU number at the time of manufacturing, therefore will be less potent by the time the product reaches your home," she says.
Most recently, two back-to-back papers were published simultaneously on September 6 in the journal Cell showing that many people can’t successfully colonize standard probiotic microbiome in their gut. The scientists also found that consuming generic probiotic strains after taking antibiotics often delayed gut bacteria and gene expression from returning to their natural "naïve" state.
Probiotics are live bacteria that are present in yogurt, other fermented foods, and in pills. They are promoted as a benefit to the human digestive system. Normally you have trillions upon trillions of bacteria within the colon. Normally we ingest bacteria every time we swallow. Many of these swallowed bacteria may be beneficial while most are simply innocuous and cause no problems. The question for everyone who takes a probiotic much beyond yogurt is whether they really are a health benefit. Here is what we know medically about probiotics.
In the gastrointestinal tract L. Plantarum can help regulate immunity and control inflammation. A 2007 study found that the probiotic could suppress an inflammatory response in the gut. Perhaps most significantly, a double blind placebo-controlled study over 4 weeks concluded that L. Plantarum 299v provided effective symptom relief, especially of abdominal pain and bloating, in patients with Irritable Bowel Syndrome [1].
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Known as the most clinically proven effective probiotic strain, Lactobacillus rhamnosus GG (otherwise known as “LGG”) has been clinically proven to maintain healthy numbers of bacteria and yeast for optimal digestive health. This powerful probiotic is also paired with some of the best probiotic strains for feminine health, making it an ideal choice for any woman that is looking for complete care from her probiotic.
There’s preliminary evidence that some probiotics are helpful in preventing diarrhea caused by infections and antibiotics and in improving symptoms of irritable bowel syndrome, but more needs to be learned. We still don’t know which probiotics are helpful and which are not. We also don’t know how much of the probiotic people would have to take or who would most likely benefit from taking probiotics. Even for the conditions that have been studied the most, researchers are still working toward finding the answers to these questions.
This smooth, slightly tangy, and sippable yogurt contains a dozen different types of live active cultures. It's also 99% lactose-free, making it easier to digest for those with intolerant tummies. "If you have lactose intolerance, start slowly on kefir as a test. If you have no symptoms, go ahead and slowly increase your intake," advises Tallmadge. Plus, with 8 to 11 grams of protein per cup (depending on the brand), it can help fill you up for around 100 calories.
Tempeh is made with fermented soybeans or grains that have been molded into a cake-like form. The nuttier, tangier cousin to tofu can be sliced for sandwiches, tossed into stir-fries, or marinated and grilled. In addition to probiotics, tempeh contains about 15 grams of protein per half-cup and is a good source of iron. Plus, soy foods contain compounds that may help keep cholesterol in check, according to a study in The American Journal of Clinical Nutrition. Palmer likes to use tempeh in place of tofu in dishes like stir-fries, salads, and side dishes.

A Seal of Approval When looking for a good probiotic, Gans advises consumers to buy from a trusted retailer and look for a seal from a third-party certifier. “Reputable probiotic supplements should list the genus, species, and strain, in addition to the number of organisms that will be alive by the use-by date and the dose on the label,” says Gans. This transparency will help consumers understand what’s in their supplement and how to best use it.
You experience that afternoon slump and reach for a candy bar or a sugar-laden coffee. Or maybe you go through your day, starting with a breakfast of doughnuts or sugary cereal, and then proceed to sodas for drinks, cookies to snack on, dessert after dinner, and finally to a nighttime snack of ice cream. You know that feeling; it’s that I-have-to-have-something-sweet-and- I-have-to-have-it-NOW feeling.
The scientists discovered that the probiotics successfully colonized the GI tracts of some people, called the "persisters," while the gut microbiomes of "resisters" expelled them. Moreover, the persister and resister patterns would determine whether probiotics, in a given person, would impact their indigenous microbiome and human gene expression. The researchers could predict whether a person would be a persister or resister just by examining their baseline microbiome and gut gene expression profile.
Yet that’s how probiotics are often offered. They can be distributed in the United States as food, supplements or drugs. The regulations for each are very different. Most people looking for probiotics don’t see the distinctions. Ideally, the ways in which we use and consume probiotics would conform to the data and evidence that back them up. That rarely happens.
“If someone has disrupted his gut microbial balance, this is where a probiotic can be of benefit,” says Gail Cresci, PhD, RD, an intestinal microbe specialist with Cleveland Clinic’s Department of Gastroenterology, Hepatology and Nutrition. “But whether it’s really going to help and whether you’re taking the right one are the big questions out there.”
Taking relatively high doses of these probiotic strains before, during, and after antibiotic treatment can help your microbiome get back on its feet: B. Lactis, B. Infantis, L. Acidophilus, L. Casei, L. Bulgaricus, L. Paracasei, L. Rhamnosus GG, and S. Boulardii. Our antibiotic combatant MegaFood MegaFlora has six of these strains, as well as eight others. One serving contains 20 billion CFUs to replenish the good bacteria.
Even if some of the bacteria in a probiotic managed to survive and propagate in the intestine, there would likely be far too few of them to dramatically alter the overall composition of one's internal ecosystem. Whereas the human gut contains tens of trillions of bacteria, there are only between 100 million and a few hundred billion bacteria in a typical serving of yogurt or a microbe-filled pill. Last year a team of scientists at the University of Copenhagen published a review of seven randomized, placebo-controlled trials (the most scientifically rigorous types of studies researchers know how to conduct) investigating whether probiotic supplements—including biscuits, milk-based drinks and capsules—change the diversity of bacteria in fecal samples. Only one study—of 34 healthy volunteers—found a statistically significant change, and there was no indication that it provided a clinical benefit. “A probiotic is still just a drop in a bucket,” says Shira Doron, an infectious disease expert at Tufts Medical Center. “The gut always has orders of magnitude more microbes.”
Better Health Review ranks Ultimate Flora as the most effective probiotic supplement. It contains 30 billion active bifidobacteria for colon health, and 20 billion lactobacilli and lactococcus cultures for the small intestine. According to Better Health Review, it contains all natural ingredients. It earns a perfect 5 score from Better Health Review, and the magazine “Vitamin Retailer” voted it best two years in a row.
Scientists are investigating probiotics, and their combined effects, by trying to classify the probiotic benefits of ingesting specific probiotic strains and understanding their role in the digestive tract. At present, the methodological and ethical limitations of human studies still make it difficult to fully understand the mechanisms of action of probiotics, but some explanations are available. Nevertheless, benefits linked to the consumption of probiotic strains have already been suggested (e.g. helping to support the immune system, help support digestive health), and others are still being investigated.
Keep in mind that when supplements contain a specific number of organisms, this number may not be what is actually within each capsule at the time of purchase. Probiotics are living organisms and can die out easily. Especially if that supplement sits on your drugstore or warehouse shelf for months or longer, the number of organisms you get may be far less than what the bottle claims. Hardier strains have a longer shelf life. Capsule strength decays faster if the probiotic has been sitting around at elevated temperatures during transport to the store. Companies actually have to produce probiotics with a much higher CFU (colony-forming units; see below) count in each capsule in order to guarantee the label potency by the expiration date.
Once GI experts realized there is more to the lower gut than first assumed, the push to understand the diverse roles these bacteria play became urgent. Many mysteries still need solving, but clinical evidence increasingly indicates that people in good health should optimize lower gut bacteria. You can accomplish this by eating prebiotics to encourage the growth of your existing gut microbes, and probiotics to add to the ones that are already there.

Another study by Elinav and his colleagues suggests that not everyone’s gut reacts the same way to probiotic pills. They studied samples of microbiomes from antibiotic users before and after they took supplements for four weeks. The good bacteria were found in the digestive tracts of some people. But in others, the bacteria were present only in stool samples, not in their digestive tracts, where they’re thought to be needed to improve health. 
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